Answer:
From their energy storage-body fat
Step-by-step explanation:
Frogs (especially terrestrial frogs) survive during the winter by going into the state of hibernation (dormant state). Since the frogs are cold-blooded animals (depend on environmental conditions), they need to find a hidden place (hibernacula) where they can survive unfavorable cold conditions. During these hibernation state, frogs slow down their activities: there is no moving, breathing, not even the heart beating. Frogs use their body fat storage as an energy source. Glucose from the liver is released in the blood and it acts as an antifreeze.